Urethane materials are commonly used as adhesives, coatings, foam fillers, foam structures, and foam cushions. From an application perspective there is no meaningful-distinction between the terms “urethane” and “polyurethane.” These materials are sometimes formulated as single part compositions and sometimes formulated as multi-part compositions that are mixed prior to application. Sometimes the urethanes are heated (“hot melted”) for applications, sometimes special curing agents such as moisture are used. Urethanes are often applied as coatings to components and are often fabricated as molded mechanical components. Urethanes are capable of forming strong bonds with other materials such as wood, glass, and metal. As a consequence urethanes are often used as adhesives.
Frequently it is desirable to detach a urethane from a component, or to separate two components that have been bonded together by a urethane adhesive. For many years methylene chloride was the “gold standard” solvent for debonding. However, this solvent has been identified as a hazardous air pollutant, and it is a suspect carcinogen. Hence, its use has been eliminated by most of industry. While a number of replacement solvents have been identified, very few approach the effectiveness of methylene chloride. Also, many of the replacement solvents are flammable and constitute hazardous wastes under the Resource Conservation and Recovery Act (RCRA) at 42 U.S.C. 6921-6939e. Other replacement materials have various shortcomings such as a pungent odor, the potential for diversion to illicit drug manufacturing, or ineffectiveness in attacking urethanes in thin bond lines. What are needed therefore are more effective and practical solvents for use in debonding urethane materials from components.